< cpp‎ | utility‎ | tuple
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Defined in header <tuple>
template< /*tuple-like*/ TTuple, /*tuple-like*/ UTuple,

          template<class> class TQual, template<class> class UQual >
    requires /* see below */

struct basic_common_reference<TTuple, UTuple, TQual, UQual>;
(since C++23)

The common reference type of two tuple-like types is a tuple consists of the common reference types of all corresponding element type pairs of both types, where the cv and reference qualifiers on the tuple-like types are applied to their element types.

The common type is defined only if

  • both TTuple and UTuple are cv-unqualified tuple-like types, and
  • either TTuple or UTuple is a std::tuple specialization, and
  • both TTuple and UTuple have the same number of elements (as determined by std::tuple_size_v), and
  • all corresponding element type pairs of TTuple and UTuple have common reference types.

[edit] Member types

Member type Definition
type std::tuple<std::common_reference_t<TQual<TTypes>..., UQual<UTypes>>...>

In the table above, TTypes... and UTypes... denotes the sequence of element types of TTuple and UTuple respectively, where each elements type of TupleLike at given index I is std::tuple_element_t<I, TupleLike>.

[edit] Example

[edit] See also

determines the common reference type of a group of types
(class template) [edit]
determines the common reference type of two pairs
(class template specialization) [edit]